This invention is directed to organosilicon compositions, and more particularly to certain silicone liquid crystals, silicone vesicles, and silicone gels.
At least as early as 1957, Plueddemann in U.S. Pat. No. 3,046,250 (Jul. 24, 1962) had prepared new polymers in the form of solutions, fluids, viscous fluids, tars, and rubbery solids, by reacting organosilicon epoxides with amine compounds. However, the systems used to prepare these new polymers were anhydrous, and even when a polar solvent such as ethanol was used, it was present at a very high solids level during the reaction, i.e., at least forty-nine percent by weight or more. No new polymers were prepared by Plueddemann in silicone fluids like (i) volatile polydimethylsiloxanes such as hexamethyldisiloxane, octamethyltrisiloxane, and decamethylcyclopentasiloxane; or (ii) nonvolatile polydimethylsiloxanes with a viscosity in the range of 5-10,000 centistoke (mm2/s).
As a result, Plueddemann was not able, and it was not Plueddeman""s intent, to prepare any new organosilicon compositions in the form of a silicone liquid crystal, silicone vesicle, or silicone gel, which are the primary focus of the present invention.
The invention relates to silicone liquid crystals, silicone vesicles, and silicone gels, formed by combining (i) an amine functional silicone or an organic amine compound, (ii) an organic epoxide containing at least two epoxy groups or an epoxy functional silicone containing at least two epoxy groups, and (iii) water.
In a second embodiment, silicone gels are formed by combining (i) an amine functional silicone or an organic amine compound, (ii) an organic epoxide containing at least two epoxy groups or an epoxy functional silicone containing at least two epoxy groups, and (iii) a silicone fluid other than the silicone defined in (i) and (ii).
A third embodiment involves forming silicone gels by combining (i) an amine functional silicone or an organic amine compound; (ii) an organic epoxide containing at least two epoxy groups or an epoxy functional silicone containing at least two epoxy groups; and (iii) a polar organic compound or a nonpolar organic compound other than the organic compounds defined in (i) and (ii), in which the polar organic compound or the nonpolar organic compound is present at a concentration to provide a level of solids less than 40 percent by weight based on the total weight of (i)-(iii), where (i) and (ii) are the solids.
One or more active ingredients can be included in any of the above embodiments.
These and other features of the invention will become apparent from a consideration of the detailed description.
Silicone liquid crystals and silicone vesicles can be prepared according to this invention by combining:
(i) 0.01-95 percent by weight of an amine functional silicone or an organic amine compound;
(ii) 0.01-95 percent by weight of an organic epoxide or an epoxy functional silicone;
(iii) 0.1-99.98 percent by weight of water; optionally
(iv) 1-30 percent by weight of a surfactant; and optionally
(v) 0.01-50 percent by weight of one or more active ingredients.
Silicone gels can be prepared according to this invention by combining:
(i) 0.1-99.89 percent by weight of an amine functional silicone or an organic amine compound;
(ii) 0.01-99.89 percent by weight of an organic epoxide or an epoxy functional silicone;
(iii) 0.1-99.89 percent by weight of a fluid which can be water, a silicone fluid other than a silicone used in (i) and (ii), a polar organic compound, or a non-polar organic compound; optionally
(iv) 1-30 percent by weight of a surfactant; and optionally
(v) 0.01-50 percent by weight of one or more active ingredients.
In one embodiment, a silicone gel composition is obtained by combining (i) an organic amine compound; (ii) an epoxy functional silicone containing at least two epoxy groups; and (iii) a polar organic compound or a nonpolar organic compound other than the organic compound at defined in (i), in which the polar organic compound or the nonpolar organic compound is present in the composition at a concentration of less than 40 percent by weight based on the total weight of (i)-(iii).
The amine functional polysiloxane used in preparing these compositions has the formula: 
wherein Rxe2x80x2 denotes an alkyl group of 1 to 30 carbons, an aryl group, an aralkyl group, or an alkaryl group, with the proviso that at least 50 percent of the total number of Rxe2x80x2 groups are methyl; Q denotes an amine functional substituent of the formula xe2x80x94Rxe2x80x3Z wherein Rxe2x80x3 is a divalent alkylene radical of 3 to 6 carbon atoms and Z is a monovalent radical selected from the group consisting of xe2x80x94NR2xe2x80x2xe2x80x3, and xe2x80x94NRxe2x80x2xe2x80x3(CH2)bNR2xe2x80x2xe2x80x3; wherein Rxe2x80x2xe2x80x3 denotes hydrogen or an alkyl group of 1 to 4 carbons, and b is a positive integer having a value of from 2 to 6; z has a value of 0 or 1; x has an average value of 25 to 3000; y has an average value of 0 to 3,000 when z is 1, y has an average value of 1 to 3,000 when z is 0.
Suitable Rxe2x80x2 groups are represented by and may be independently selected from among methyl, ethyl, propyl, isopropyl, butyl, isobutyl, phenyl, xenyl, benzyl, phenylethyl, and tolyl, with the proviso that at least fifty percent of the Rxe2x80x2 groups are methyl.
The alkylene radicals represented by Rxe2x80x3 may include trimethylene, tetramethylene, pentamethylene, xe2x80x94CH2CH(CH3)CH2xe2x80x94, and xe2x80x94CH2CH2CH(CH3)CH2xe2x80x94. Siloxanes where Rxe2x80x3 is a trimethylene or an alkyl substituted trimethylene radical such as xe2x80x94CH2CH(CH3)CH2xe2x80x94, are preferred.
Alkyl groups of 1 to 4 carbon atoms as represented by Rxe2x80x2xe2x80x3 include methyl, ethyl, propyl, isopropyl, butyl, and isobutyl.
Useful Z radicals include the unsubstituted amine radical xe2x80x94NH2, alkyl substituted amine radicals such as xe2x80x94NHCH3, xe2x80x94NHCH2CH2CH2CH3, and xe2x80x94N(CH2CH3)2; and aminoalkyl substituted amine radicals such as xe2x80x94NHCH2CH2NH2, xe2x80x94NH(CH2)6NH2, and xe2x80x94NHCH2CH2CH2N(CH3)2.
When z is zero, the silicone polymer has only pendent amine functional substituents in the polymer chain. When z is one, the silicone polymer may have only terminal amine functional substituents or both terminal and pendent amine functional substituents in the polymer chain. Preferably, x may vary from a value of 25 to 500, and y may vary from zero to 100 when z is one and from one to 100 when z is zero. Most preferably, the value of x+y is in the range of about 50 to 1,000.
The amine content, i.e., the number of amine functional groups in the molecule of the amine functional polysiloxane, is generally expressed as mol percent amine, and this is determined according to the relationship y/DPxc3x97100, where y is the value of integer y in the above formula for the amine functional polysiloxane, and the Degree of Polymerization (DP) is x+y+2 which indicates the chain length of the amine functional polysiloxane.
Such amine functional polysiloxanes are well known in the art and available commercially from sources such as the Dow Corning Corporation, Midland, Mich. USA.
When it is desired to use an organic amine compound instead of an amine functional polysiloxane, reference may be had to Plueddemann""s U.S. Pat. No. 3,046,250 for a detailed list of some representative organic amine compounds, among which are for example, ammonia, diethylene triamine, ethylene diamine, methane diamine, m-phenylene diamine, methylene dianiline, benzohydrazide, guanidine, benzidene sulfone, thioacetamide, piperazine, p-amino benzoic acid, thiosemicarbizide, allanturic acid, p,pxe2x80x2-thiodianiline, p-bromophenyl hydrazine, benzene pentamine, and N,Nxe2x80x2-dimethyl ethylene diamine.
Organic epoxides containing at least two epoxy groups, i.e., diepoxides, suitable for use herein include compositions such as ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerine diglycidyl ether, triglycidyl ether, propylene glycol diglycidyl ether, butanediol diglycidyl ether; 1,2,3,4-diepoxybutane; 1,2,4,5-diepoxypentane; 1,2,5,6-diepoxyhexane; 1,2,7,8-diepoxyoctane; 1,3-divinylbenzene diepoxide; 1,4-divinylbenzene diepoxide; 4,4xe2x80x2-isopropylidene diphenol diglycidyl ether, and hydroquinone diglycidyl ether.
Other polyglycidyl ethers of alkane polyols, polyglycidyl ethers of poly(alkylene glycols), diepoxy alkanes, diepoxy aralkanes, and polyphenol polyglycidyl ethers, can also be used herein.
Two especially preferred organic epoxides containing at least two epoxy groups are shown below, in which n is a positive integer determining the molecular weight of the epoxide. 
When it is desirable to use an epoxy functional silicone containing at least two epoxy groups instead of an organic epoxide containing at least two epoxy groups, a suitable epoxy functional silicone of the general structure shown below can be used, in which x represents an integer of one or more. 
Such epoxy functional silicones are well known in the art and available commercially from sources such as the Dow Corning Corporation, Midland, Mich. USA. Typically, such silicones have a viscosity ranging from 1 to about 200 centistoke (mm2/s) and molecular weights of about 300-6,000.
If desired, organic epoxides and epoxy functional silicones containing a single epoxy group can be included as an additional component, in order to control the cross link density and the overall molecular weight of the silicone gel.
U.S. Pat. No. 5,948,855 (Sep. 7, 1999) contains an extensive lists of appropriate silicone fluids which can be used, among which are for example, (i) volatile polydimethylsiloxanes such as hexamethyldisiloxane, octamethyltrisiloxane, and decamethylcyclopentasiloxane; and (ii) nonvolatile polydimethylsiloxanes. These volatile and nonvolatile polydimethylsiloxanes include silicone fluids having a viscosity ranging from 0.65 to 10,000 centistoke (mm2/s).
U.S. Pat. No. 5,948,855 also contains an extensive list of nonpolar organic compounds which can be used, among which are fragrances such as musk and myrrh, and mixtures thereof. In addition, nonpolar organic compounds such as natural oils derived from animal, vegetable, or mineral sources are also suitable. Most preferred are modern cosmetic oils known to be safe for cosmetic purposes such as almond oil, apricot kernel oil, avocado oil, cacao butter (theobroma oil), carrot seed oil, castor oil, citrus seed oil, coconut oil, corn oil, cottonseed oil, cucumber oil, egg oil, jojoba oil, lanolin oil, linseed oil, mineral oil, mink oil, olive oil, palm kernel oil, peach kernel oil, peanut oil, rapeseed oil, safflower oil, sesame oil, shark liver oil, soybean oil, sunflower seed oil, sweet almond oil, tallow (beef) oil, tallow (mutton) oil, turtle oil, vegetable oil, whale oil, and wheat germ oil.
Some polar organic compounds which can be used are monohydroxy alcohols such as ethyl alcohol and isopropyl alcohol; diols and triols such as propylene glycol, 2-methyl-1,3-propane diol HOCH2CH(CH3)CH2OH, 1,2-hexanediol CH3(CH2)3CH(OH)CH2OH, and glycerol; glycerol esters such as glyceryl triacetate (triacetin), glyceryl tripropionate (tripropionin), and glyceryl tributyrate (tributyrin); and polyglycols such as polyethylene glycols and polypropylene glycols, among which are PPG-14 butyl ether C4H9[OCH(CH3)CH2]14OH.
The surfactant can be a nonionic, cationic, anionic, or a mixture of such surfactants. Most preferred are organic nonionic surfactants, but the nonionic surfactant can be one containing a silicon atom. Most preferred are alcohol ethoxylates R2xe2x80x94(OCH2CH2)cOH, most particularly fatty alcohol ethoxylates. Fatty alcohol ethoxylates typically contain the characteristic group xe2x80x94(OCH2CH2)cOH which is attached to fatty hydrocarbon residue R2 which contains about eight to about twenty carbon atoms, such as lauryl (C12), cetyl (C16) and stearyl (C18). While the value of xe2x80x9ccxe2x80x9d may range from 1 to about 100, its value is typically in the range of 2 to 40.
Some examples of suitable nonionic surfactants are polyoxyethylene (4) lauryl ether, polyoxyethylene (5) lauryl ether, polyoxyethylene (23) lauryl ether, polyoxyethylene (2) cetyl ether, polyoxyethylene (10) cetyl ether, polyoxyethylene (20) cetyl ether, polyoxyethylene (2) stearyl ether, polyoxyethylene (10) stearyl ether, polyoxyethylene (20) stearyl ether, polyoxyethylene (21) stearyl ether, polyoxyethylene (100) stearyl ether, polyoxyethylene (2) oleyl ether, and polyoxyethylene (10) oleyl ether. These and other fatty alcohol ethoxylates are commercially available under such names as ALFONIC(copyright), BRIJ, GENAPOL(copyright), LUTENSOL, NEODOL(copyright), RENEX, SOFTANOL, SURFONIC(copyright), TERGITOL(copyright), TRYCOL, and VOLPO.
One especially useful nonionic surfactant is polyoxyethylene (23) lauryl ether, a product sold under the name BRIJ 35L by ICI Surfactants, Wilmington, Del. It has an HLB of about 16.9.
Cationic surfactants useful in the invention include compounds containing quaternary ammonium hydrophilic moieties in the molecule which are positively charged, such as quaternary ammonium salts represented by R3R4R5R6N+Xxe2x88x92 where R3 to R6 are alkyl groups containing 1-30 carbon atoms, or alkyl groups derived from tallow, coconut oil, or soy; and X is halogen such as chlorine or bromine, or X can be a methosulfate group. Most preferred are dialkyldimethyl ammonium salts represented by R7R8N+(CH3)2Xxe2x88x92, where R7 and R8 are alkyl groups containing 12-30 carbon atoms, or alkyl groups derived from tallow, coconut oil, or soy; and X is halogen or a methosulfate group. Monoalkyltrimethyl ammonium salts can also be employed, and are represented by R9N+(CH3)3Xxe2x88x92 where R9 is an alkyl group containing 12-30 carbon atoms, or an alkyl group derived from tallow, coconut oil, or soy; and X is halogen or a methosulfate group.
Representative quaternary ammonium salts are dodecyltrimethyl ammonium bromide (DTAB), didodecyldimethyl ammonium bromide, dihexadecyldimethyl ammonium chloride, dihexadecyldimethyl ammonium bromide, dioctadecyldimethyl ammonium chloride, dieicosyldimethyl ammonium chloride, didocosyldimethyl ammonium chloride, dicoconutdimethyl ammonium chloride, ditallowdimethyl ammonium chloride, and ditallowdimethyl ammonium bromide. These and other quaternary ammonium salts are commercially available under such names as ADOGEN, ARQUAD, SERVAMINE, TOMAH, and VARIQUAT.
Examples of anionic surfactants include sulfonic acids and their salt derivatives; alkali metal sulfosuccinates; sulfonated glyceryl esters of fatty acids such as sulfonated monoglycerides of coconut oil acids; salts of sulfonated monovalent alcohol esters such as sodium oleyl isothionate; amides of amino sulfonic acids such as the sodium salt of oleyl methyl tauride; sulfonated products of fatty acid nitriles such as palmitonitrile sulfonate; sulfonated aromatic hydrocarbons such as sodium alpha-naphthalene monosulfonate; condensation products of naphthalene sulfonic acids with formaldehyde; sodium octahydro anthracene sulfonate; alkali metal alkyl sulfates such as sodium lauryl (dodecyl) sulfate CH3(CH2)11OSO3Na; ether sulfates having alkyl groups of eight or more carbon atoms; and alkylaryl sulfonates having one or more alkyl groups of eight or more carbon atoms.
Commercial anionic surfactants useful in this invention include triethanolamine linear alkyl sulfonate sold under the name BIO-SOFT N-300 by the Stepan Company, Northfield, Ill.; sulfates sold under the name POLYSTEP by the Stepan Company; and sodium n-hexadecyl diphenyloxide disulfonate sold under the name DOWFAX 8390 by The Dow Chemical Company, Midland, Mich.
The liquid crystals, vesicles, and gels, prepared according to the invention may contain one or more active ingredients in one or more of their phase(s). Some representative aqueous and polar organic compound soluble active ingredients are (i) Vitamins, (ii) drugs including activated antiperspirant salts such as aluminum chlorohydrate and aluminum-zirconium trichlorohydrate, or (iii) xcex1-hydroxy acids such as glycolic acid, lactic acid, tartaric acid, and citric acid, i.e., fruit acids. U.S. Pat. No. 5,948,855 contains an extensive list of aqueous and polar organic compound soluble Vitamins and drugs which can be used, among which are Vitamin C, Vitamin B1, Vitamin B2, Vitamin B6, Vitamin B12, niacin, folic acid, biotin, and pantothenic acid.
U.S. Pat. No. 5,948,855 also contains an extensive list of nonpolar oil soluble active ingredients which can be carried in a phase(s) of the silicone fluid or nonpolar organic compound, such as vitamins and drugs among which are Vitamin A1, RETINOL, C2-C18 esters of RETINOL, Vitamin E, TOCOPHEROL, esters of Vitamin E, RETINYL ACETATE, RETINYL PALMITATE, RETINYL PROPIONATE, xcex1-TOCOPHEROL, TOCOPHERSOLAN, TOCOPHERYL ACETATE, TOCOPHERYL LINOLEATE, TOCOPHERYL NICOTINATE, TOCOPHERYL SUCCINATE, and mixtures thereof.
Other common types of active ingredients can also be included in any phase(s), if desired, such as a fragrance or a sunscreen, i.e., an UV absorber/UV light stabilizer.
Silicone liquid crystals, silicone vesicles, and silicone gels of the invention can be prepared at room temperature using simple propeller mixers, turbine-type mixers, Brookfield counter-rotating mixers, or homogenizing mixers. No special equipment or processing conditions are generally required. Often, simple hand shaking is sufficient. Heat facilitates their formation, and so these compositions can be prepared at temperatures ranging from 25-100xc2x0 C.